Bit former



March 14, 1944; H E; MCKEEN I 2,344,361 l BIT FORME-R Filed March 24, 1942 2] ll" l1 'Ilm 26 /6 INVEN'T'OR HCLYOIJE NCA/CETZ @QP/MJ Pat ented Mar. 14, 1944 p VVVColumbia, Canada Application Marchas 1942, serial N11-.436,055 s Ciaims. (el. vrs-'95) Thisnvention relates to'nevvv and useful limprovementsrin a bitv'formentits primary object beingjto provide means whereby rockdrill bits may be formed; VSaid means including a pair of interchangeable blocks which may be refaced; re-

newed or repaired whenV damaged or worn in use.

A further object of the invention is to provide a holding frame or box for the said blocks wherein the same are retained in position while the bit is formed thereon.

A still further object is to devise spring means to grip the said blocks and hold the same in spaced apart relation to each other in the box, said spring means being attached to said box.

Another object of the invention is to construct a former comprising a plurality of blocks having more than one face and designed to be re-arranged to present another working face when necessary thus increasing the life of the device.

With these and other objects in view that may appear while the description proceeds the invention consists in the novel construction and arrangement of parts as hereinafter more specifically set forth, claimed and shown in the accompanying drawing forming part of this application and in which- Fig. 1 is a perspective view of my invention.

Fig. 2 is a plan View of the same.

Fig. 3 is a plan view of the holding frame or box showing the spring retaining means therein.

Fig. 4. is a side elevation of one of the former blocks.

Fig. 5 is a plan View of the same showing a modification in the construction of the face.

Referring more in detail to the drawing in which similar reference characters designate corresponding parts throughout the several views it will be seen the invention consists of a pair of former blocks III one of which is a right and the other a left hand.

The blocks are of symmetrical design and arranged so that either face may be used thus permitting reversing the same when one face becomes Worn or damaged. The working face II of the blocks is provided with a raised portion I2 on one end thereof on the inner end of which are a number of steps I3. It will be seen that the steps are angularly positioned with respect to the center line of the blocks. The angle to which these steps are constructed Will correspond to the angle of the working edge of the bit I4, shown dotted in Fig. 2. The inner longitudinal edge I5 of the blocks is rounded as shown to accommodate and form the shank of the bit.

In the alternative view shown in Fig. 5, the

steps I3 are shown convergingtoward thecenter and both theedges I5"ar"e`rounded as shown. With this typeof block an additional face is provided thus adding to the economic life of the block. v 1" -The holding frame or box I6 comprises a base I1 having parallel sides I8 of corresponding length to the blocks. Two parallel slots I9 are cut in the said base adjacent the closed end of the box and the inner ends 20 of the said slots are bevelled inward toward the top and angularly disposed with respect to the center line in correspondence to the steps of the raised portions I2 on the faces of the former blocks I0. A tongue 2I is formed between the slots forming means to bring the blocks into working position in the frame. The end 22 is closed and the center of the upper edge is lowered as shown at 23 to permit the bit shank I4 being placed in blocks I0.

It will be seen in Fig. 4, where the frame is shown in a dotted line that the slots are designed to receive the said raised portions I2 of the former blocks thereby positioning the blocks in spaced parallel relation to receive the bit to be sharpened therebetween.

The spring retaining means for the blocks consists of a U-shaped spring 24 having its outer ends 25 turned inwards at an angle with respect to the centerline thereof. The spring is secured centrally to the end 22 of the frame by a bolt or rivet 26. The spring arms 21 are arranged to normally diverge from the center so that the tension thereof will hold the blocks securely against the side walls I 8 of the frame thus preventing inadvertent movement of the blocks when in use.

In operation, the bit former die assembly shown in Fig. 1 is mounted in the sharpening machine with a complementary bit forming die mounted thereabove and movable towards the rst die assembly whereby a bit placed between the die assemblies will be forged into the proper shape. An air hammer or other hammering device actuates the movable die assembly to produce the desired force to hammer the bit between the forming blocks until it is properly shaped. The bit to be sharpened is rst heated to the proper temperature and is then placed centrally of the former blocks with the shank resting in the recess 23 of the closed end of the holding box. The working edges of the bit wings rest on the steps I3, as shown in dotted lines in Fig. 2, and under the hammer action of the movable die assembly the working edges are forged into proper shape.

It is believed that the construction and advantages of the structure shown may be apparent from the foregoing paragraphs taken in conjunction with the accompanying drawing without further detailed description.

bottom wall thereof at one end, a pair of former blocks having raised portions on their upper and lower faces at opposite ends, the inner ends of the raised portions being serrated to receive the While the preferred embodiment or the inven- 5 working edge of the bit wings, said former blocks tion has been disclosed it is understood that being adapted to t in said frame with the raised minor changes in the details of construction, portions on the lower faceshseated in the slots combination and arrangement of co-operating of the bottom wall, and an'expansible spring disparts may be resorted to within the scope of what posed between said former blocks for holding the is claimed without departing from the spirit of l0 blocks in spaced relation.' l e the invention. 3.`In a bit former die, the combination of a I claim: holding frame having spaced parallel slots in the 1. In a bit former die the combination of a` bottom wall thereof at one end, a pair of former holding frame having spaced parallel slots in its blocks having raised portions on their upper and bottom wall at one end, a pair of former blocks l5 lower faces at opposite ends, the inner ends of adapted to fit in said frame having raised porthe raised'portions being serrated to receive the tions on their upper and lower faces at opposite working edge of the bit wings, said former blocks ends, the raised portions on the lower faces bebeing adapted to fit in said frame with the raised ing adapted to seat in the slots in the bottom of portions on the lower faces seated in the slots of said frame whereby the former blocks are held 20 the bottom wall, and a U-shaped spring attached in spaced parallel relation, said raised portions to one end of saidframe having diverging varms having a series of steps at their inner ends to rein contacting engagement with the inner sides of eeive theA working edge of the bit when placed on said blocks adapted toA exert an outward force on the upper faces of the former blocks. o said blocks to hold them in spaced parallel rela- 2. In a bit former die the combination of a 25 tion.

holding frame having spaced parallel slots in the HAROLD EDWARD MCKEEN. 

